Indications for emergency intravenous pyelography (IVP) in blunt abdominal trauma: a reappraisal

Renal imaging in the diagnostic evaluation of blunt abdominal trauma is a valuable adjunct, but its indications remain controversial. Classic indications for the use of emergency intravenous pyelography (IVP) have been liberal, but more recently the medical need, cost effectiveness, and potential risks of this approach have been questioned in favor of a more selective approach. This retrospective study was undertaken to reassess the value of emergency IVP in blunt abdominal trauma and to test the hypothesis that post-traumatic microscopic hematuria, without other physical or laboratory findings, can safely be managed by observation alone. With the aid of the computerized Trauma Registry at the University of Virginia Medical Center, 50 consecutive patients undergoing emergency IVP for blunt abdominal trauma were identified over a 1-year period. A significantly abnormal IVP was found in six of seven patients with gross hematuria (86%). No patient of 43 with microscopic hematuria had a clinically significant abnormality (p less than 0.001, Chi-square). Three patients in the latter group (7%) had IVP findings which were anatomically abnormal but clinically insignificant, while an equal number (7%) had IVP's which were inadequate or misleading. Emergency IVP is useful in patients with specific indications and gross hematuria, but patients with post-traumatic microscopic hematuria alone may be safely followed by observation. Abdominal CT scanning is emerging as a more useful study than IVP for renal imaging in the stable patient with blunt abdominal trauma.